Roman Julian Calendar. The roman calendar, evolving from an early system devised by romulus, initially consisted of 304 days with ten months. The roman calendar was a complex system that included a mix of lunar and solar.

The julian calendar, also known as the old style calendar, was a significant historical timekeeping system that was introduced by julius caesar in 46 bc and remained the. The julian calendar, also known as the old style calendar, was established by julius caesar in 46 bc, to replace the roman calendar which was in use.